1. Field of the Invention
The present invention relates to a method for producing a plastic molding which is provided on an outer surface thereof with a foam with a skin and foaming die apparatus for producing the same.
2. Description of the Related Art
For instance, a conventional instrument panel for an automobile is usually made of a core 93 which is provided on a part or entirety of the outer surface thereof with a pad comprising a foam 91 with a skin, from an protective or decorative viewpoint, as shown in FIG. 10.
There are known methods for producing such a plastic molding product having on the outer surface thereof an outer foam with a skin.
For instance, a foam with a skin (foam assembly), made of laminated layers of a mounting base, a foaming member, and an outer skin is prepared in advance and the foam assembly thus prepared is secured to the core by screws or the like at predetermined positions.
In another known method, an outer skin member which is provided on the outer periphery thereof with an edge (skirt) is disposed on a die surface of a lower die with the skirt being located on the outer periphery of the molding cavity of the lower die; and a core is disposed on a die surface of an upper die. When the upper and lower dies are brought into an operative position, the skirt is held between the upper and lower dies. In this state, a foaming material is poured and foamed between the core and the outer skin member. The skirt is finally cut and removed.
However, in the former method, an additional process to secure the foam assembly to the core is necessary. Moreover, since the molding obtained includes the heavy mounting base of the foam assembly which is usually made of a steel plate, the molding is heavy as a whole. In addition to the foregoing, a clearance tends to be produced at a boundary portion of the peripheral edge of the foam assembly and the core, thus leading to a poor appearance of the product.
In the latter method, the foaming material tends to flow onto the outside of the molding through the skirt of the outer skin member, thus resulting in a formation of a flash. Furthermore, an additional process to cut and remove the skirt is needed. The residual foaming material on the skirt that has been cut makes it difficult to reuse the skirt, thus resulting in a waste of the material.